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What Primers

Posted: Fri Dec 07, 2007 6:31 pm
by augnmike
My new rifle build is finally done and I can pick it up in ten days. It's a 6x47 (6mm-.222) and I have loaded up some rounds with the primers I use for my .204 they are CCI 450 Small Rifle Magnum Primers. My question is are these the best choice for this new round or is there something else I should consider? Talked to Tom who said I was ok with these but didn't get into other possible choices or what to consider when choosing a primer. I am loading Win 748, H322 and IMR4895 to try in this round.

Re: What Primers

Posted: Fri Dec 07, 2007 7:49 pm
by acloco
Any primer will work...question of how well and how accurate is the issue.

You work up loads....just like you did with your 204.


Seems that all of the small case centerfires that I shoot seem to prefer the CCI450's. The hard primer cup helps in all (17 remington, 204, 223, & 223 AI). I also see to get the most consistent FPS over the Pact chronograph with the 450's as well.

PICS! We need PICS of your new build!

Re: What Primers

Posted: Sat Dec 08, 2007 8:58 am
by augnmike
Soon as I pick it up I will post some pics of it. Thanks again for the info. The gunsmith made me a "chamber" that exactly matches my actual chamber using a cut off part of my barrel. He showed me how to use a marker pen on the shoulder and bullet of a loaded round and then insert it into the "chamber" he made then turn the round inside the fake chamber to see where it has rub marks in the ink on the shoulder and bullet ogive. Apparently I am looking for about equal faint lines on both. It's way over my head given my experience.

Re: What Primers

Posted: Mon Dec 17, 2007 6:57 am
by Rick in Oregon
augnmike: The smith did you well. That piece of gear is what we commonly call a "chamber gauge", and will allow to tailor your bullet style and seating depth perfectly to that chamber.

If you use a jewler's loop or magnifying glass, you can insert a bullet into the gauge and actually see where it makes contact with the lands (if it has a cutaway). If it does not have a cutaway as shown below on one of mine, you'll still be able to get your seating depth into, or ready to 'kiss' the lands. Either way, you have what every custom gunsmith should give to their customer once the chambering job is finished. I've got one for every custom barrel I own, and it really helps in the accuracy department.

Image

Above is a 17 Acklely Hornet with a 20gr Berger in my Pac-Nor chamber gauge, that one made up by Broad Creek Rifle Works in DE.

You'll want to get a Stoney Point Seating Depth Tool to compliment your gauge to control and measure seating depth. You're on your way to accuracy, my friend. ;)

Re: What Primers

Posted: Mon Dec 17, 2007 8:13 am
by skipper
Mine doesn't have the cut out like Rick's. Here's how I do it.

1) Insert a fire formed case into the gauge and take a precise measurement with your calipers. (the case must be fire formed or it may be shorter than your actual chamber headspace) You will want to measure the case and gauge together so you will know the exact Overall Length of the case in the gauge. Let's take a hypothetical measurement, for an example, of 2.9965"

2) Seat a bullet long and insert that case into the gauge and take another measurement. It should be longer that the measurement you took in step 1. Let's say it measured 3.000"

3) Keep seating the bullet deeper into the case until it measures exactly the same as your measurement in step 1. (2.9965") Your bullet is now just touching the lands.

If you want to jam the bullet into the lands then just add the amount you want to jam onto the measurement you took in step 1 and use that measurement instead of the measurement you took in step 1. 2.9965 + .010 = 3.0065 Now when you chamber these rounds the will be forced into the lands by .010” if you have enough neck tension so they aren’t just pushed father into the case neck.

If your die has a micrometer top with .001” gradient marks it will take the guess work out of the process. You can even load shorter than the lands by a specific amount by loading to just touching the lands and then lowering the seating stem by the desired amount you want to load short of the lands.

Once throat erosion sets in you will need the Stoney Point. For that matter, you will need the Stoney Point to know when throat erosion sets in.

Re: What Primers

Posted: Mon Dec 17, 2007 9:39 am
by augnmike
You guys are awesome! I am still pretty new at this but the descriptions were so good even I get it. I pic the rifle up today and will take some pics. My gauge isn't cut away but I sill follow the info Skipper gave. Question, I assume fire forming just means cases I have shot through the new rifle already? Also as a follow up I assume that means no case trimming other wise it would screw it all up right? So I fire some rounds through the new gun, put one of those cases in the gauge measure the gauge and case together, seat a bullet long and begin to seat it until it reaches a distance of slightly over the original measurement? That puts me up against the lands. If I want to be slightly shorter then just seated it a hair deeper. Am I on target?

Re: What Primers

Posted: Mon Dec 17, 2007 5:36 pm
by skipper
augnmike

You pretty much have it. I don't consider my cases fully fire formed until they have been shot twice. A couple of points though. Trimming your cases should not disrupt the fire formed fit. All you cases should be trimmed to the exact same length for consistency. Check them after firing the first few times to see if they are growing. You can allow them to grow until they reach about .005 from the end of your chamber, but keep them trimmed the same length. Another note is that once fire formed don't try to shoot those cases in any other rifle. They are custom fitted to your chamber. They may not even fit in another rifle. I use Norma cases in my tight neck chamber and they don't grow. In my son's XR-100 the Remington and Winchester cases do grow.

Don't full length size after fire forming. Neck size only so you don't ruin that fire formed fit. You will also want to get a bushing neck sizing die so you can vary the neck tension by changing bushings. My rifle likes more neck tension. Right now I'm using the .223 bushing.

With a custom chamber gauge you will sure want to pick up a good seating die with a micrometer top like the Redding. Those Redding dies are hard to beat. The micrometer has .001" marks so you can get pretty close just using the marks alone. The Redding dies will also help control your run out. Good Luck.

Re: What Primers

Posted: Mon Dec 17, 2007 8:37 pm
by augnmike
Skipper I had a heck of a time finding dies for this caliber. There are no nice dies even made for it like there are for my .204. Where would I get a neck sizing die for a 6x47? As far as the nice bullet seating die with the micrometer top they aren't out there.

Re: What Primers

Posted: Mon Dec 17, 2007 9:38 pm
by skipper
Contact Redding or Wilson and see if they can make you some dies specific for your rifle. They might want a few dummy rounds. I bet they will be glad to make you some.

Re: What Primers

Posted: Tue Dec 18, 2007 9:11 am
by augnmike
Skipper thanks for the tip. I didn't realize you could call them and have dies made up. I will do that today. I have Redding dies now so maybe I will call them. What exactly should I ask for? I currently have their standard dies Full Length resizer and bullet seater. If you don't mind be specific about what I should order since this is all still new to me. Thanks

Re: What Primers

Posted: Tue Dec 18, 2007 3:15 pm
by skipper
You can probably get the dies you need at Midway without having to go the custom route. They carry Redding 6X47 Lapua dies.

http://www.midwayusa.com/eproductpage.e ... t=11082005

This set has the dies you will need. The next step up would be to go with Wilson dies and an arbor press.

Re: What Primers

Posted: Tue Dec 18, 2007 5:41 pm
by augnmike
My understanding is that the Lapua won't work for me. Mine is a 6mm-.222 rem mag aka 6x47.

Re: What Primers

Posted: Tue Dec 18, 2007 7:34 pm
by skipper
I have to know where you are finding .222 Rem Mag cases. Those things are hard to come by any more.

Re: What Primers

Posted: Tue Dec 18, 2007 7:36 pm
by jo191145
augnmike

Question for you. Are the necks of your brass (222Rem Mag?) already fireformed or expanded to 6mm or are they still .224 Makes a real big difference in your next step.

Your right. Finding a set of dies for the 6X47 could be difficult. Your gunsmith might be the best place to start.
Do you know if the reamer he used was his or a rental?
The 6x47 is an older wildcat. Therefor its quite possible reamer dimensions could vary greatly. Hopefully not but one never knows.
Redding did make dies for it at one time. How'd you make out with them. Probably your best bet.
Your smith could make a set of dies if he owns the reamer. Probably a very expensive proposition but they would be exact dimensions (read BR quality) Might be cheaper if you gave him a set of 222Rem Mag dies to ream.-Good Luck

Edit to add another thought.
Seeing as the 6x47 is an old BR round its highly likely the reamer was too. That being the case you'll probably need to turn the necks on your cases after they're formed to 6mm. No turn necks are a relatively new thing in the BR world.
Did your smith mention the neck size?

Skippers right. Brass is gonna be tough to find. Unless you have a secret stash grab it up quick.
I wonder if 204 brass would survive the transformation. You'd need to push the shoulders back quite a bit. Not sure how much off the top of my head.

Re: What Primers

Posted: Tue Dec 18, 2007 10:59 pm
by augnmike
brass is easy to get from Midway or Midsouth. I bought 500 rounds of unfired .222 Rem Mag Remington brass before I had the build completed.

http://www.midwayusa.com/ebrowse.exe/br ... 670***9013***

http://www.midsouthshooterssupply.com/i ... 5023003100

Here are links to the brass Midway is back ordered now but Midsouth has brass now. 500 should last me a while.

I have several friends with this caliber and they are using the same brass, FL resizing it and it's ready to go.

Also I have Redding dies for the 6x47 but they are the standard dies no micometer top on the seater and no neck sizer just the FL.